Vertebroplasty and kyphoplasty are surgical procedures for treating osteoporotic fractures and the like. In these procedures a cement-like material is introduced, as by injection, into the fractured bone, e.g., the vertebral body. A disadvantage of conventional vertebroplasty is that it generally does not result in restoration of the height of compressed vertebral bodies. Kyphoplasty includes additional steps prior to and after introduction of the cement-like material wherein an inflatable balloon tamp is placed within the fracture and inflated to support the bone at a desired dimension for introduction of the cement, with the tamp being removed before the cement is introduced. Kyphoplasty sometimes helps in regards to height restoration, but desires improvement in that it does not offer consistent results and is a more invasive and complicated procedure. Accordingly, improvement is desired in the treatment of fractures, and particularly in the treatment of compressed vertebral bodies where height restoration or maintenance is desired.
In accordance with one aspect, the invention relates to vertebral lift device. In a preferred embodiment, the device includes an expandable member made of a bio-compatible material and having a plurality of interconnected structural members. The expandable member has a first dimension for insertion thereof into a damaged vertebral body having a damaged dimension. The interconnected structural members of the expandable member are expandable to a second dimension substantially corresponding to dimensions of the vertebral body prior to its damage. The expandable member defines a void area within a periphery defined by the structural members when the expandable member is expanded to the second dimension for receiving a restoration agent. A covering configured to substantially cover the exterior of the expandable member is provided to inhibit leakage of the restoration agent received within the void area.
In another aspect, the invention relates to a method for restoring a vertebral body. In a preferred embodiment, the method includes the steps of introducing the covered expandable member into the damaged vertebral body with the expandable member configured in its first dimension; expanding the expandable member to its second dimension within the damaged vertebral body to substantially restore the vertebral body to its pre-damage dimensions; maintaining the expandable member in the vertebral body at its second dimension and introducing a restoration agent into the void area of the expandable member; maintaining the restoration agent within the expandable member to support the vertebral body at a restored state; and maintaining the expandable member in the vertebral body at its second dimension to assist the restoration agent in maintaining the dimensions of the vertebral body in the restored state.